European Patent Application No. 0 057 407 describes a valve, in particular a fuel injection valve, having a swirl body downstream from a valve closing body and upstream from a spray orifice; this swirl body imparts a swirl component to the fuel to be sprayed. The resulting swirling flow yields a to better fuel turbulence, so that finer fuel atomization is achieved in comparison with a constricted spray flow.
Likewise, a fuel injection valve having a turbulence-producing is device upstream from an outlet orifice of the valve is described in Japanese Patent Application No. 57-183559. This turbulence-producing device has a plurality of swirl grooves, all of which have the same orientation and serve to impart a swirl component to the fuel for an improved turbulence. In addition, atomization of fuel can be further improved using tangential air inlet channels with which a swirl is also imparted to the air.
In addition, swirl channels, swirl grooves or other swirl devices are also conventionally provided in valves and are situated, for example, directly on the valve needle or on the valve closing body, i.e., they are also upstream from the valve seat face. All these conventional swirl arrangements have in common the fact that all the fluid to be sprayed out is influenced by the swirl elements in only one direction or orientation.
An arrangement for atomizing liquids is also described in European Patent Application No. 0 435 973, which is provided on the outlet side of an injection valve. The liquid to be sprayed flows from an outlet orifice of the injection valve and then flows through the atomizer arrangement which is supplied with air through air lines. The atomizer arrangement contains two turbulence-producing planes, which follow one another axially and into which the air is injected. The turbulence-producing planes are designed so that opposite directions of rotation are imparted to the two developing air turbulences. The fluid, in particular a fuel, is also entrained by the turbulent air, and a swirl is imparted to the fluid to some extent, although this is achieved only through the energy stored in the air. Due to the opposite directions of rotation of the turbulent flows, the rotational movement of the overall flow as it leaves the atomizer arrangement is eliminated.